diff --git a/services/topuptool/current/app/src/agebd_topuptool/service.py b/services/topuptool/current/app/src/agebd_topuptool/service.py
index 3754214..69d6843 100644
--- a/services/topuptool/current/app/src/agebd_topuptool/service.py
+++ b/services/topuptool/current/app/src/agebd_topuptool/service.py
@@ -4,13 +4,14 @@ from time import perf_counter
 import numpy as np
 from epics import PV, dbr
 
-from agebd.pv import LocalPVLink, get_pv_class
+from agebd.pv import LocalPVLink, get_pv_class, get_pv_external_class
 from agebd.service.pvs import BasePVs
 from agebd.utils import printgetversion
 
 __version__ = printgetversion(__file__)
 
 PV = get_pv_class()
+PV_EXTERNAL = get_pv_external_class()
 
 
 class PVs(BasePVs):
@@ -33,35 +34,35 @@ class PVs(BasePVs):
     scrubbing = PV("AGEBD-TOPUPTOOL:CONTROL-SCRUB.VAL")
 
     # Input PVs
-    vac_all = PV("ARIVA-VMAVE-ALL:PRESS-MAX.VAL")
-    vac_acc = PV("ARIVA-VMAVE:PRESS-MAX.VAL")
-    vac_fe = PV("ARIVA-VMAVE-FE:PRESS-MAX.VAL")
-    # cur = PV('AGEBD-DBPM3CURR:CURRENT-AVG.VAL')
-    cur = PV("ARS07-DPCT-0000:CURR.VAL")
-    injguard = PV("AGEBD-INJECTIONGUARD:CHECK-SUM.VAL")
+    vac_all = PV_EXTERNAL("ARIVA-VMAVE-ALL:PRESS-MAX.VAL")
+    vac_acc = PV_EXTERNAL("ARIVA-VMAVE:PRESS-MAX.VAL")
+    vac_fe = PV_EXTERNAL("ARIVA-VMAVE-FE:PRESS-MAX.VAL")
+    # cur = PV_EXTERNAL('AGEBD-DBPM3CURR:CURRENT-AVG.VAL')
+    cur = PV_EXTERNAL("ARS07-DPCT-0000:CURR.VAL")
+    injguard = PV_EXTERNAL("AGEBD-INJECTIONGUARD:CHECK-SUM.VAL")
 
-    injactive = PV("AGEBD-PARAMS:INJECTION-ACTIVE")
+    injactive = PV_EXTERNAL("AGEBD-PARAMS:INJECTION-ACTIVE")
 
-    tau = PV("AGEBD-PARAMS:LIFETIME.VAL")
+    tau = PV_EXTERNAL("AGEBD-PARAMS:LIFETIME.VAL")
 
-    fpfb_adc = PV("ARSGE-CECL-FPFB:BEAM-DUMP-ABS-ADC-DATA")
-    fpfb_max = PV("ARSGE-CECL-FPFB:FPFB-BEAM-DUMP-THR")
+    fpfb_adc = PV_EXTERNAL("ARSGE-CECL-FPFB:BEAM-DUMP-ABS-ADC-DATA")
+    fpfb_max = PV_EXTERNAL("ARSGE-CECL-FPFB:FPFB-BEAM-DUMP-THR")
 
     # Regulated PVs
-    trig_master = PV("AGETI-CVME-MASTER-TMA:SR-Inj-Status-Sel.VAL")
-    trig_guntxb = PV("ALIRF-VME-A-GUN:CH1-MODE.VAL")
-    trig_gunevt = PV("AGETI-CVME-MASTER-TMA:Evt-LI-Gun-Ena-Sel.VAL")
-    trig_booinj = PV("AGETI-CVME-MASTER-TMA:Evt-BO-Inj-Ena-Sel.VAL")
-    trig_boormp = PV("AGETI-CVME-MASTER-TMA:Evt-Old-BO-HW-Ena-Sel.VAL")
-    trig_booext = PV(
+    trig_master = PV_EXTERNAL("AGETI-CVME-MASTER-TMA:SR-Inj-Status-Sel.VAL")
+    trig_guntxb = PV_EXTERNAL("ALIRF-VME-A-GUN:CH1-MODE.VAL")
+    trig_gunevt = PV_EXTERNAL("AGETI-CVME-MASTER-TMA:Evt-LI-Gun-Ena-Sel.VAL")
+    trig_booinj = PV_EXTERNAL("AGETI-CVME-MASTER-TMA:Evt-BO-Inj-Ena-Sel.VAL")
+    trig_boormp = PV_EXTERNAL("AGETI-CVME-MASTER-TMA:Evt-Old-BO-HW-Ena-Sel.VAL")
+    trig_booext = PV_EXTERNAL(
         "AGETI-CVME-MASTER-TMA:Evt-BO-Ext-Ena-Sel.VAL"
     )  # Alias AGETI-CVME-MASTER-TMA:Evt-10
-    trig_rininj = PV(
+    trig_rininj = PV_EXTERNAL(
         "AGETI-CVME-MASTER-TMA:Evt-SR-Inj-Ena-Sel.VAL"
     )  # Alias AGETI-CVME-MASTER-TMA:Evt-26
-    gun_grid = PV("ALIRF-GUN-GRID:V-SET.VAL")
-    pinger_v = PV("ARS01-MKIK-0320:CTRL-ON-OFF.VAL")
-    pinger_h = PV("ARS01-MKIK-0290:CTRL-ON-OFF.VAL")
+    gun_grid = PV_EXTERNAL("ALIRF-GUN-GRID:V-SET.VAL")
+    pinger_v = PV_EXTERNAL("ARS01-MKIK-0320:CTRL-ON-OFF.VAL")
+    pinger_h = PV_EXTERNAL("ARS01-MKIK-0290:CTRL-ON-OFF.VAL")
 
     topup_dt = PV("AGEBD-TOPUPTOOL:TOPUP-DELTAT.VAL")
     topup_dI = PV("AGEBD-TOPUPTOOL:TOPUP-DELTAI.VAL")
@@ -69,23 +70,6 @@ class PVs(BasePVs):
 
     def __init__(self, service_name: str, pv_factory=PV):
         super().__init__(service_name, pv_factory)
-        PV = pv_factory
-
-        # TODO: can we do this cleaner? Maybe mechanism for
-        # settings initial values in dev mode (e.g. ini file)
-        if isinstance(self.onoff, LocalPVLink):
-            self.onoff.value = True
-
-        # Option 2:
-        ## Service specific PVs from dedicated IOC
-        self.my_pv2 = PV("AGEBD-TOPUPTOOL:BO")  # TODO: is this a good PV to use?
-
-        ## Service specific PVs from other IOCs
-        # ...
-
-        # TODO: class attribute names usually lowercase
-        # usually it is advisable to trigger the mainloop of a service on changes of certain PVs:
-        self.CallbackPV = PV("AGEBD-TOPUPTOOL:CALLBACK", auto_monitor=dbr.DBE_VALUE)  # TODO: ok?
 
 
 class Service: